Submission #431915

#	Time	Username	Problem	Language	Result	Execution time	Memory
431915		amunduzbaev	Regions (IOI09_regions)	C++14	0 / 100	3901 ms	131076 KiB

regions

/* made by amunduzbaev */
 
#include "bits/stdc++.h"
 
using namespace std;
 
//~ #include <ext/pb_ds/assoc_container.hpp>
//~ #include <ext/pb_ds/tree_policy.hpp>
//~ using namespace __gnu_pbds;
//~ template<class T> using oset = tree<T, 
//~ null_type, less_equal<T>, rb_tree_tag, 
//~ tree_order_statistics_node_update>;
 
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define NeedForSpeed ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define vv vector
#define mem(arr, v) memset(arr, v, sizeof arr)
#define int long long
#define degub(x) cout<<#x<<" : "<<x<<"\n"
#define GG cout<<"here"<<endl;
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii; 
typedef vector<int> vii;
typedef vector<pii> vpii;
template<class T> bool umin(T& a, const T& b) { return a > b ? a = b, true : false; }
template<class T> bool umax(T& a, const T& b) { return a < b ? a = b, true : false; }
template<int sz> using tut = array<int, sz>;
void usaco(string s) { freopen((s+".in").c_str(),"r",stdin);  
	freopen((s+".out").c_str(),"w",stdout); NeedForSpeed }
 
const int N = 2e5+5;
const int mod = 1e9+7;
const ll inf = 1e18;
const ld Pi = acos(-1);
const int B = 500;
 
#define MULTI 0
int n, m, k, t, q, ans, res, a[N];
int heavy[N], last[N], id[N], cnt[N];
int bs[N / B + 10][N];
int sb[N][N / B + 10];
vii edges[N];
vpii cmp[N];

//~ BIG_SMALL BIG_BIG
int cur;
void bsdfs(int u, int p = -1, int cnt = 0){
	if(id[a[u]] == cur) cnt++;
	bs[cur][a[u]] += cnt;
	for(auto x : edges[u]) bsdfs(x, u, cnt);
}

//~ SMALL_BIG
map<int, int> sbdfs(int u, int p = -1){
	map<int, int> cnt;
	if(id[a[u]]) cnt[id[a[u]]]++;
	for(auto x : edges[u]) {
		map<int, int> tmp = sbdfs(x, u);
		if(sz(tmp) > sz(cnt)) swap(cnt, tmp);
		for(auto x : tmp) cnt[x.ff] += x.ss;
	}
	
	if(!id[a[u]]){
		for(auto x : cnt) sb[a[u]][x.ff] += x.ss;
	} return cnt;
}

int tin[N], tout[N];
void dfs(int u, int p = -1){
	tin[u] = t++;
	for(auto x : edges[u]) dfs(x, u);
	tout[u] = t - 1;
}

bool par(int a, int b) { return (tin[a] <= tin[b] && tout[b] <= tout[a]); }

void solve(int t_case){
	cin>>n>>m>>q;
	cin>>a[1];
	for(int i=2;i<=n;i++){
		int p; cin>>p>>a[i];
		edges[p].pb(i);
	}
	
	for(int i=1;i<=n;i++) cnt[a[i]]++;
	int last = 1;
	for(int i=1;i<=m;i++){
		if(cnt[i] > B) id[i] = last++;
	}
	
	for(int i=1;i<last;i++) cur = i, bsdfs(1);
	sbdfs(1), dfs(1);
	for(int i=1;i<=n;i++) cmp[a[i]].pb({tin[i], tout[i]});
	for(int i=1;i<=m;i++) sort(all(cmp[i]));

	for(int i=1;i<=q;i++){
		int x, b; cin>>x>>b;
		if(id[a[x]]) cout<<bs[id[a[x]]][a[b]]<<endl;
		else if(id[a[b]]) cout<<sb[a[x]][id[a[b]]]<<endl;
		else { res = 0; 
			//~ SMALL_SMALL
			for(auto tt : cmp[a[x]]){
				int lx = lb(all(cmp[a[b]]), mp(tt.ff, -1ll)) - cmp[a[b]].begin();
				int rx = ub(all(cmp[a[b]]), mp(tt.ss, tt.ss)) - cmp[a[b]].begin();
				res += rx - lx;
			} cout<<res<<endl;
		}
	}
}

signed main(){
	NeedForSpeed
	if(MULTI){
		int t; cin>>t;
		for(int t_case = 1; t_case <= t; t_case++) solve(t_case);
	} else solve(1);
	return 0;
}

Compilation message (stderr)

regions.cpp: In function 'void usaco(std::string)':
regions.cpp:38:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 | void usaco(string s) { freopen((s+".in").c_str(),"r",stdin);
      |                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
regions.cpp:39:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   39 |  freopen((s+".out").c_str(),"w",stdout); NeedForSpeed }
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 15
• Subtask 2: 0 / 85